Originally a terminal was a screen and a keyboard, looking very
much like a standard desktop computer in the days before flat
screens and windowing systems. There are still a surprising
number of these around. The important point is that it was
(is) a text-only interface to the
computer. You got 25 lines of 80 fixed-width white-on-black or
green-on-black characters, no fonts, no colours,
and no mouse; maybe reverse-video as a form of
highlighting (see Figure C.1).
Figure C.1: Text-only display terminals
Images courtesy of Wikipedia.
Left: IBM 3279 display by
Retro-Computing Society of Rhode Island (CC BY-SA 3.0);
Right: DEC VT100 terminal by Jason
Scott (Flickr IMG_9976, CC BY 2.0), at
the Living Computer Museum (apparently connected to the
museum’s DEC PDP-11/70).
Nowadays the word usually means a ‘virtual
terminal’: a window that behaves like a terminal —
25 lines of 80 fixed-width characters in monochrome (see Figure C.2). It’s window into the heart of your
computer. Even though you still have all your other windows
visible, it knows nothing about them and can’t interact with
them (much; maybe copy and paste). But instead of being a
padded cell, most terminals can do things many other windows
can’t, like handling files in bulk, or to a schedule, or
unattended, even forcing things to happen even when the
graphical world outside has got itself jammed solid.
C.1.1 So where is the terminal window?
- Apple Macintosh OS X
- Microsoft Windows
Click on the Windows or Start button,
(in older versions it’s called )
- UNIX and GNU/Linux
In most graphical interfaces, click on the menu
(in some systems it’s called
When you have finished using the terminal, it’s good
practice to type exit (and
C.1.2 Using the terminal window
On a physical terminal you usually have to log in first
(very much like today: username and password). In a terminal
window this isn’t usually necessary (see Figure C.2).
Figure C.2: Virtual terminal in a window
In this example I’m logged into a computer called
nimrod with my username
peter. The system prompt is the
directory name plus a dollar sign (the tilde indicates
that I’m in my home directory system). For visibility, I
underlined in red here the commands I typed, one to
change to my Documents folder, and
one to run XƎLATEX on the
The first thing you see is the
prompt (usually a dollar sign or
percent sign, or maybe a greater-than pointer
C:\> like MS-DOS
used to use). When the prompt appears, you can type an
instruction (command) and press the Enter
key at the end of the line to send if off to the computer
for processing. Until you press Enter, the
computer has no idea you’ve finished typing: you
Enter at the end of each line of command
for it to take effect.
The results, if any, are displayed on the screen, and
the prompt is displayed again ready for your next command.
Some commands don’t have any output: if you change directory
or delete a file, for example, you just get another prompt.
There’s no message confirming the action, and no check to
see if you really meant it. You said to do it, and it’s
C.1.3 How do I know what commands to type?
You have to learn or be told, or you have to look up
what you want to do in a manual (or on the web). Terminals
don’t have menus (there are simply far too many commands to
fit in menus), and while UNIX and GNU/Linux systems
(including Apple Macintosh OS X) have an online
manual, it’s not searchable in the normal meaning of the
word: you have to know in advance the name of the program
command you want to look up.
Having said that, unless you plan on using the terminal
for a lot of other work, there are really only half a dozen
commands you need to be familiar with. The most important of
these are the obvious ones: latex, pdflatex, xelatex, or latexmk; plus makeindex and biber or bibtex depending on whether or
not you have an index, and how you want your bibliography
formatted. Each command is the single-word short name of a
program, and is followed by the name of the LATEX file you
want to typeset.
A few other commands are pretty essential: they have
nothing to do with LATEX — these are housekeeping or
file-management commands and are built into every computer.
There are a lot more of them but these are the ones you will
Change Directory, followed
by the name of a folder or directory. This makes sure
you are in the right directory (folder) for what you
want to do. Terminals always start up in your Home or
Login directory, so you will almost always want to
type this as your first command, eg
$ cd Documents/reports/quarterly
Note that you have to know
which directory you need to change into: the computer
cannot know or guess. In Windows systems you have to
use the backslash instead of the normal slash to
separate folders and filenames.
This command shows you the contents of a file,
screen by screen. It’s not an editor, so you can’t
change the contents, but it’s a fast way to have a
quick look at a small file without editing it. You
press the spacebar to go to the next page, or the
Enter key to move line by line. Press
q to stop the program and get back to
the command prompt.
$ more mythesis.aux
- del or rm
ReMove, followed by the
name of the file or folder you want to get rid of —
del is the Windows
command and rm is for
all other desktop systems.
C:\Documents\reports\quarterly> del mythesis.aux
There is no check or safety-catch, and no Trash or
Wastebasket to retrieve accidentally-deleted files
from. When you delete a file, it’s really gone,
immediately and forever.
Finishes your terminal session and closes the window.